
jQuery.extend( {

    // Counter for holding the number of active queries
    active: 0,

    // Last-Modified header cache for next request
    lastModified: {},
    etag: {},

    ajaxSettings: {
        url: ajaxLocation,
        type: "GET",
        isLocal: rlocalProtocol.test( ajaxLocParts[ 1 ] ),
        global: true,
        processData: true,
        async: true,
        contentType: "application/x-www-form-urlencoded; charset=UTF-8",
        /*
        timeout: 0,
        data: null,
        dataType: null,
        username: null,
        password: null,
        cache: null,
        throws: false,
        traditional: false,
        headers: {},
        */

        accepts: {
            "*": allTypes,
            text: "text/plain",
            html: "text/html",
            xml: "application/xml, text/xml",
            json: "application/json, text/javascript"
        },

        contents: {
            xml: /\bxml\b/,
            html: /\bhtml/,
            json: /\bjson\b/
        },

        responseFields: {
            xml: "responseXML",
            text: "responseText",
            json: "responseJSON"
        },

        // Data converters
        // Keys separate source (or catchall "*") and destination types with a single space
        converters: {

            // Convert anything to text
            "* text": String,

            // Text to html (true = no transformation)
            "text html": true,

            // Evaluate text as a json expression
            "text json": jQuery.parseJSON,

            // Parse text as xml
            "text xml": jQuery.parseXML
        },

        // For options that shouldn't be deep extended:
        // you can add your own custom options here if
        // and when you create one that shouldn't be
        // deep extended (see ajaxExtend)
        flatOptions: {
            url: true,
            context: true
        }
    },

    // Creates a full fledged settings object into target
    // with both ajaxSettings and settings fields.
    // If target is omitted, writes into ajaxSettings.
    ajaxSetup: function( target, settings ) {
        return settings ?

            // Building a settings object
            ajaxExtend( ajaxExtend( target, jQuery.ajaxSettings ), settings ) :

            // Extending ajaxSettings
            ajaxExtend( jQuery.ajaxSettings, target );
    },

    ajaxPrefilter: addToPrefiltersOrTransports( prefilters ),
    ajaxTransport: addToPrefiltersOrTransports( transports ),

    // Main method
    ajax: function( url, options ) {

        // If url is an object, simulate pre-1.5 signature
        if ( typeof url === "object" ) {
            options = url;
            url = undefined;
        }

        // Force options to be an object
        options = options || {};

        var

            // Cross-domain detection vars
            parts,

            // Loop variable
            i,

            // URL without anti-cache param
            cacheURL,

            // Response headers as string
            responseHeadersString,

            // timeout handle
            timeoutTimer,

            // To know if global events are to be dispatched
            fireGlobals,

            transport,

            // Response headers
            responseHeaders,

            // Create the final options object
            s = jQuery.ajaxSetup( {}, options ),

            // Callbacks context
            callbackContext = s.context || s,

            // Context for global events is callbackContext if it is a DOM node or jQuery collection
            globalEventContext = s.context &&
            ( callbackContext.nodeType || callbackContext.jquery ) ?
                jQuery( callbackContext ) :
                jQuery.event,

            // Deferreds
            deferred = jQuery.Deferred(),
            completeDeferred = jQuery.Callbacks( "once memory" ),

            // Status-dependent callbacks
            statusCode = s.statusCode || {},

            // Headers (they are sent all at once)
            requestHeaders = {},
            requestHeadersNames = {},

            // The jqXHR state
            state = 0,

            // Default abort message
            strAbort = "canceled",

            // Fake xhr
            jqXHR = {
                readyState: 0,

                // Builds headers hashtable if needed
                getResponseHeader: function( key ) {
                    var match;
                    if ( state === 2 ) {
                        if ( !responseHeaders ) {
                            responseHeaders = {};
                            while ( ( match = rheaders.exec( responseHeadersString ) ) ) {
                                responseHeaders[ match[ 1 ].toLowerCase() ] = match[ 2 ];
                            }
                        }
                        match = responseHeaders[ key.toLowerCase() ];
                    }
                    return match == null ? null : match;
                },

                // Raw string
                getAllResponseHeaders: function() {
                    return state === 2 ? responseHeadersString : null;
                },

                // Caches the header
                setRequestHeader: function( name, value ) {
                    var lname = name.toLowerCase();
                    if ( !state ) {
                        name = requestHeadersNames[ lname ] = requestHeadersNames[ lname ] || name;
                        requestHeaders[ name ] = value;
                    }
                    return this;
                },

                // Overrides response content-type header
                overrideMimeType: function( type ) {
                    if ( !state ) {
                        s.mimeType = type;
                    }
                    return this;
                },

                // Status-dependent callbacks
                statusCode: function( map ) {
                    var code;
                    if ( map ) {
                        if ( state < 2 ) {
                            for ( code in map ) {

                                // Lazy-add the new callback in a way that preserves old ones
                                statusCode[ code ] = [ statusCode[ code ], map[ code ] ];
                            }
                        } else {

                            // Execute the appropriate callbacks
                            jqXHR.always( map[ jqXHR.status ] );
                        }
                    }
                    return this;
                },

                // Cancel the request
                abort: function( statusText ) {
                    var finalText = statusText || strAbort;
                    if ( transport ) {
                        transport.abort( finalText );
                    }
                    done( 0, finalText );
                    return this;
                }
            };

        // Attach deferreds
        deferred.promise( jqXHR ).complete = completeDeferred.add;
        jqXHR.success = jqXHR.done;
        jqXHR.error = jqXHR.fail;

        // Remove hash character (#7531: and string promotion)
        // Add protocol if not provided (#5866: IE7 issue with protocol-less urls)
        // Handle falsy url in the settings object (#10093: consistency with old signature)
        // We also use the url parameter if available
        s.url = ( ( url || s.url || ajaxLocation ) + "" )
            .replace( rhash, "" )
            .replace( rprotocol, ajaxLocParts[ 1 ] + "//" );

        // Alias method option to type as per ticket #12004
        s.type = options.method || options.type || s.method || s.type;

        // Extract dataTypes list
        s.dataTypes = jQuery.trim( s.dataType || "*" ).toLowerCase().match( rnotwhite ) || [ "" ];

        // A cross-domain request is in order when we have a protocol:host:port mismatch
        if ( s.crossDomain == null ) {
            parts = rurl.exec( s.url.toLowerCase() );
            s.crossDomain = !!( parts &&
                ( parts[ 1 ] !== ajaxLocParts[ 1 ] || parts[ 2 ] !== ajaxLocParts[ 2 ] ||
                    ( parts[ 3 ] || ( parts[ 1 ] === "http:" ? "80" : "443" ) ) !==
                    ( ajaxLocParts[ 3 ] || ( ajaxLocParts[ 1 ] === "http:" ? "80" : "443" ) ) )
            );
        }

        // Convert data if not already a string
        if ( s.data && s.processData && typeof s.data !== "string" ) {
            s.data = jQuery.param( s.data, s.traditional );
        }

        // Apply prefilters
        inspectPrefiltersOrTransports( prefilters, s, options, jqXHR );

        // If request was aborted inside a prefilter, stop there
        if ( state === 2 ) {
            return jqXHR;
        }

        // We can fire global events as of now if asked to
        // Don't fire events if jQuery.event is undefined in an AMD-usage scenario (#15118)
        fireGlobals = jQuery.event && s.global;

        // Watch for a new set of requests
        if ( fireGlobals && jQuery.active++ === 0 ) {
            jQuery.event.trigger( "ajaxStart" );
        }

        // Uppercase the type
        s.type = s.type.toUpperCase();

        // Determine if request has content
        s.hasContent = !rnoContent.test( s.type );

        // Save the URL in case we're toying with the If-Modified-Since
        // and/or If-None-Match header later on
        cacheURL = s.url;

        // More options handling for requests with no content
        if ( !s.hasContent ) {

            // If data is available, append data to url
            if ( s.data ) {
                cacheURL = ( s.url += ( rquery.test( cacheURL ) ? "&" : "?" ) + s.data );

                // #9682: remove data so that it's not used in an eventual retry
                delete s.data;
            }

            // Add anti-cache in url if needed
            if ( s.cache === false ) {
                s.url = rts.test( cacheURL ) ?

                    // If there is already a '_' parameter, set its value
                    cacheURL.replace( rts, "$1_=" + nonce++ ) :

                    // Otherwise add one to the end
                    cacheURL + ( rquery.test( cacheURL ) ? "&" : "?" ) + "_=" + nonce++;
            }
        }

        // Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
        if ( s.ifModified ) {
            if ( jQuery.lastModified[ cacheURL ] ) {
                jqXHR.setRequestHeader( "If-Modified-Since", jQuery.lastModified[ cacheURL ] );
            }
            if ( jQuery.etag[ cacheURL ] ) {
                jqXHR.setRequestHeader( "If-None-Match", jQuery.etag[ cacheURL ] );
            }
        }

        // Set the correct header, if data is being sent
        if ( s.data && s.hasContent && s.contentType !== false || options.contentType ) {
            jqXHR.setRequestHeader( "Content-Type", s.contentType );
        }

        // Set the Accepts header for the server, depending on the dataType
        jqXHR.setRequestHeader(
            "Accept",
            s.dataTypes[ 0 ] && s.accepts[ s.dataTypes[ 0 ] ] ?
                s.accepts[ s.dataTypes[ 0 ] ] +
                ( s.dataTypes[ 0 ] !== "*" ? ", " + allTypes + "; q=0.01" : "" ) :
                s.accepts[ "*" ]
        );

        // Check for headers option
        for ( i in s.headers ) {
            jqXHR.setRequestHeader( i, s.headers[ i ] );
        }

        // Allow custom headers/mimetypes and early abort
        if ( s.beforeSend &&
            ( s.beforeSend.call( callbackContext, jqXHR, s ) === false || state === 2 ) ) {

            // Abort if not done already and return
            return jqXHR.abort();
        }

        // aborting is no longer a cancellation
        strAbort = "abort";

        // Install callbacks on deferreds
        for ( i in { success: 1, error: 1, complete: 1 } ) {
            jqXHR[ i ]( s[ i ] );
        }

        // Get transport
        transport = inspectPrefiltersOrTransports( transports, s, options, jqXHR );

        // If no transport, we auto-abort
        if ( !transport ) {
            done( -1, "No Transport" );
        } else {
            jqXHR.readyState = 1;

            // Send global event
            if ( fireGlobals ) {
                globalEventContext.trigger( "ajaxSend", [ jqXHR, s ] );
            }

            // If request was aborted inside ajaxSend, stop there
            if ( state === 2 ) {
                return jqXHR;
            }

            // Timeout
            if ( s.async && s.timeout > 0 ) {
                timeoutTimer = window.setTimeout( function() {
                    jqXHR.abort( "timeout" );
                }, s.timeout );
            }

            try {
                state = 1;
                transport.send( requestHeaders, done );
            } catch ( e ) {

                // Propagate exception as error if not done
                if ( state < 2 ) {
                    done( -1, e );

                    // Simply rethrow otherwise
                } else {
                    throw e;
                }
            }
        }

        // Callback for when everything is done
        function done( status, nativeStatusText, responses, headers ) {
            var isSuccess, success, error, response, modified,
                statusText = nativeStatusText;

            // Called once
            if ( state === 2 ) {
                return;
            }

            // State is "done" now
            state = 2;

            // Clear timeout if it exists
            if ( timeoutTimer ) {
                window.clearTimeout( timeoutTimer );
            }

            // Dereference transport for early garbage collection
            // (no matter how long the jqXHR object will be used)
            transport = undefined;

            // Cache response headers
            responseHeadersString = headers || "";

            // Set readyState
            jqXHR.readyState = status > 0 ? 4 : 0;

            // Determine if successful
            isSuccess = status >= 200 && status < 300 || status === 304;

            // Get response data
            if ( responses ) {
                response = ajaxHandleResponses( s, jqXHR, responses );
            }

            // Convert no matter what (that way responseXXX fields are always set)
            response = ajaxConvert( s, response, jqXHR, isSuccess );

            // If successful, handle type chaining
            if ( isSuccess ) {

                // Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
                if ( s.ifModified ) {
                    modified = jqXHR.getResponseHeader( "Last-Modified" );
                    if ( modified ) {
                        jQuery.lastModified[ cacheURL ] = modified;
                    }
                    modified = jqXHR.getResponseHeader( "etag" );
                    if ( modified ) {
                        jQuery.etag[ cacheURL ] = modified;
                    }
                }

                // if no content
                if ( status === 204 || s.type === "HEAD" ) {
                    statusText = "nocontent";

                    // if not modified
                } else if ( status === 304 ) {
                    statusText = "notmodified";

                    // If we have data, let's convert it
                } else {
                    statusText = response.state;
                    success = response.data;
                    error = response.error;
                    isSuccess = !error;
                }
            } else {

                // We extract error from statusText
                // then normalize statusText and status for non-aborts
                error = statusText;
                if ( status || !statusText ) {
                    statusText = "error";
                    if ( status < 0 ) {
                        status = 0;
                    }
                }
            }

            // Set data for the fake xhr object
            jqXHR.status = status;
            jqXHR.statusText = ( nativeStatusText || statusText ) + "";

            // Success/Error
            if ( isSuccess ) {
                deferred.resolveWith( callbackContext, [ success, statusText, jqXHR ] );
            } else {
                deferred.rejectWith( callbackContext, [ jqXHR, statusText, error ] );
            }

            // Status-dependent callbacks
            jqXHR.statusCode( statusCode );
            statusCode = undefined;

            if ( fireGlobals ) {
                globalEventContext.trigger( isSuccess ? "ajaxSuccess" : "ajaxError",
                    [ jqXHR, s, isSuccess ? success : error ] );
            }

            // Complete
            completeDeferred.fireWith( callbackContext, [ jqXHR, statusText ] );

            if ( fireGlobals ) {
                globalEventContext.trigger( "ajaxComplete", [ jqXHR, s ] );

                // Handle the global AJAX counter
                if ( !( --jQuery.active ) ) {
                    jQuery.event.trigger( "ajaxStop" );
                }
            }
        }

        return jqXHR;
    },

    getJSON: function( url, data, callback ) {
        return jQuery.get( url, data, callback, "json" );
    },

    getScript: function( url, callback ) {
        return jQuery.get( url, undefined, callback, "script" );
    }
} );